With the markets so volatile, many investors might be tempted to head for the exits. But in these nervous times, there are smart moves you can make to protect your portfolio. CNBC asked the experts what they would buy--and sell--in this type of environment. Here's what they're telling us.

From commodities and construction materials to interest rates and mortgage lenders, the state of real estate is at the forefront of most business and financial debates. But some say opportunities still exist -- if you know where to look. CNBC's crack team of reporters dug into the real estate market from every angle. Here is a sampling of what they found.

Key sectors like the homebuilders could continue to take a serious hit. But Cramer said it doesn’t have to be that way. Here are two things he thinks could save the market.Investing can be confusing. Luckily, Cramer has mapped out some road rules for all you Home Gamers trying to navigate the jungle that is Wall Street. Think of it as "Mad Money 101" –- some fundamental advice to keep in mind as you play the market. Whether you're a first time investor or a seasoned financier, it's always good to remember the basics.

Cramer likes to say there’s always a bull market somewhere, but tonight he played the role of the ultimate bear.Investing can be confusing. Luckily, Cramer has mapped out some road rules for all you Home Gamers trying to navigate the jungle that is Wall Street. Think of it as "Mad Money 101" –- some fundamental advice to keep in mind as you play the market. Whether you're a first time investor or a seasoned financier, it's always good to remember the basics.

Bad news in the housing market this week was enough to rock the stock market right off its foundations. Existing home sales, new home sales, homebuilder earnings reports, no one expected them to be bright, but the numbers cast a heavy shadow on any optimism for a quick recovery in housing.

The slaughterhouse that has been the U.S. housing market for the past few months got bloodier on Thursday as several industry leaders reported worse results, July home sales fell more than expected and stocks throughout the sector hit multiyear lows.

How are some home builder CEOs reacting to the current housing market? Donald R. Horton, CEO D.R. Horton: “Market conditions in the homebuilding industry continue to be challenging as inventory levels of both new and existing homes remain at historically high levels. Increased use of sales incentives continues to put pressure on profit margins. In addition, home price appreciation over the past few years, higher interest rates and tightened credit standards in the mortgage industry are all negatively impacting affordability.”

Pulte Homes on Wednesday reported a second-quarter loss of $2.01, in the positive end of the home builder's July 17 guidance: It had predicted a loss of $2 to $2.10 per share. Quarterly revenue was $2.02 billion, largely in-line with forecasts.

Next week, no fewer than six major public home builders will report their quarterly earnings, all right around the same day that the U.S. Dept. of Commerce reports its New Home Sales data for the month of June. I doubt either will be very heartening for investors.

If you're going to use this sell-off as a buying opportunity, stick with stocks that deal in hard metrics.Investing can be confusing. Luckily, Cramer has mapped out some road rules for all you Home Gamers trying to navigate the jungle that is Wall Street. Think of it as "Mad Money 101" –- some fundamental advice to keep in mind as you play the market. Whether you're a first time investor or a seasoned financier, it's always good to remember the basics.

Pulte Homes, the No. 3 U.S. home builder, said Tuesday it expects to report a second-quarter loss from continuing operations in the range of $2.00 to $2.10 and said new orders were down 20 percent from a year earlier.

A key measure of industry sentiment on the U.S. market for new homes fell to its lowest point in more than 16 years, a trade group said Tuesday, as builders struggled with rising inventories of unsold houses across the country.

Speculation that Warren Buffett could buy a stake in Hovnanian sent the homebuilders up. But on "Street Signs" today Cramer explained why there's a more likely target. Investing can be confusing. Luckily, Cramer has mapped out some road rules for all you Home Gamers trying to navigate the jungle that is Wall Street. Think of it as "Mad Money 101" –- some fundamental advice to keep in mind as you play the market. Whether you're a first time investor or a seasoned financier, it's always good to remember the basics.